The purpose of the present study is to clarify the changes of choroidal circulation developing in the selective injuries of the outer layer of the retina. One, 2, 3 weeks and 3 months after intravenous administration of Monoiodoacetic acid in the rabbits, choroidal vessels were observed using indocyanine green angiography (ICG). The diameter of retinal arterioles decreased significantly at 3 weeks and 3 months after the treatment and hypofluorescence in the background was observed at 3 months. Histological examination revealed significant decrease in choriocapillaris at 3 weeks, a thickening of the endothelial cytoplasma and a disappearance of fenestration in choriocapillaris after 3 months. These histological findings were considered to be a cause of hypofluorescence of background in ICG. The results suggest that the selective damage of the outer layer of the retina induce changes in the choroidal circulation.